1. Field of the Invention
The present invention relates to laser systems and processing methods, and, more particularly, to a multi-color harmonic synthesized laser system for laser processing and a laser processing method using multi-color harmonic synthesized laser.
2. Description of Related Art
In the development of micro-nano technology and optoelectronic industry, high energy laser beams have been applied in the fabrication of micro electro mechanical systems, optoelectronic products and biomedical micro fluid chips such as high molecular weight material and silicon chip processing, electronic packages and drilling of circuit boards.
Generally, there are two high energy laser beam processing mechanisms, a photo-thermal mechanism and a photo-chemical mechanism. In the photo-thermal mechanism, high energy laser beams with high power density are used as a thermal source to be focused on an object in an extremely short time period, the energy absorbed on the surface of the object is introduced into the object via the thermal conduction, then a part of the object is melted or vaporized by sufficient heat, and the laser beams or a working station is moved for further processing. In the photo-chemical mechanism, the bonding in the material to be processed is broken by the high energy laser beams having photon energy, such that ablation is performed on the material, wherein it is easier to break the bonding in the material by the laser beams with shorter wavelength. In addition, in the laser ablation mechanism, high energy laser beams are absorbed by the material, and photons make electrons hop between energy levels and break bonding in a molecule, so as to perform precise ablation on the material.
In the high energy laser beam processing, the material is processed by the laser beams according to the energy absorption, thermal diffusion and melting point of the material. For example, ablation is performed on various materials by the laser beam with different frequencies, and the laser beams with different wave shapes may have various ablation efficiencies on the same material. Therefore, there is a need to provide a corresponding laser beam in response to various materials or requirements of processing so as to improve efficiency of laser processing.